Journal Citation Reports (JCR), the popular tool for looking up journal impact factors, is now available online . On our wish list for many years, we are finally able to subscribe to this resource thanks to grant funding. JCR Online is one of the Web of Knowledge databases along with Web of Science, BIOSIS, and Zoological Record.

JCR Online provides metrics on several thousand journals in the sciences and social sciences. The metric that authors find most valuable is the impact factor. Briefly, this is a measure of how often articles in a particular journal are cited. A journal whose articles receive a large number of citations is said to be a “high impact” journal in its field. Researchers use this information when deciding where to submit manuscripts for publication, and to demonstrate that their work has been highly visible.

In addition to the impact factor, JCR Online provides a number of other journal metrics:

Article Half-life: an indicator of how frequently older articles are still cited

Self-Citation: a reference to an article from the same journal

Five Year Impact Factor: the average citation rates calculated over five years

Eigenfactor: a five-year measure of the influence of journals by considering scholarly literature as a network of journal-to-journal relationships

In JCR Online, you can also view broad subject categories (e.g., Psychiatry) to find the journals in those areas with the highest impact factors. Compiling this data takes time. The database is updated each summer based on data from the previous complete publication year – so the current edition is based on 2007 data.

It is important to note that journal impact factors are just one measure of the merits of a journal or of an individual’s work. The UCSD Biomedical Library offers workshops and consultations on citation and impact searching for both journals and individual authors’ work; the next scheduled workshop is on April 23, 12-1 pm. To sign up, or for more information about our workshops, visit our workshop page.